Cam lock for cantilever mounting device

ABSTRACT

A cantilever mounting device includes a front member on which an object is mounted and a back member for attachment to a load-bearing surface. A first arm is connected to the back member to form a rotatable first joint. A second arm is connected to the first arm to form a rotatable second joint. The front member is connected to the second arm to form a rotatable third joint. The first joint includes a first cam including a first lever and a first shaft for connecting the back member to the first arm. The first cam allows rotation about an axis of the first joint when the first lever is set to a first adjustment position. The first cam does not allow rotation about the axis of the first joint when the first lever is set to a first locked position.

BACKGROUND OF THE INVENTION

1. Field of the Invention

This invention relates to tension adjustment for a cantilever mountingdevice.

2. Description of Related Art

Flat panel displays have become increasingly popular in homeentertainment systems. Generally, flat panel displays have a limitedviewing angle, thus making the positioning of the display important to aviewer. Flat panel displays are typically placed on stands or aremounted to a wall by flat panel mounting devices. These mounting devicesinclude articulating joints and are conventionally preset with anoptimal joint/tilt tension during manufacturing to the joints of thearticulating components and tilt mechanisms. The preset tension allowsthe flat panel mounting device to steadily and predictably hold adisplay in place. However, periodic adjustment is required to readjustthe tension of the joints and tilt mechanism to maintain a desiredviewing position. Furthermore, if a user decides to change a viewingposition of the display, the present joint tension may first need to beloosened to allow repositioning of the mounting device.

Conventionally, the end user is required to make manual adjustments tothe joints using specialized tools to provide the articulatingcomponents with the correct amount of tension or friction to hold themounting device in place. However, users without proper tools mustresort to professional installers to provide periodic tensioningadjustment. In either case, the purchase of tools or services is costlyand inconvenient. Therefore, a tension adjustment of the mounting devicehas become difficult. The present solutions do not provide the abilityto quickly and conveniently maintain the proper operation of a mountingdevice.

SUMMARY OF THE INVENTION

Various embodiments of the present invention overcome these drawbacks ofthe prior art and provide a cantilever mounting device havingarticulating joints and a cam for allowing adjustment of the jointtension by a flip of a lever from a locked position to an adjustmentposition. The adjustment position allows the adjustment of tension at acorresponding articulating joint. In this manner, the repositioning ofthe mounting device to a desired viewing angle is provided. The presentinvention is not limited to mounting flat-panel displays as any displaysuitable for mounting can be utilized.

Accordingly, one embodiment of the invention is a cantilever mountingdevice that includes a front member on which an object is mounted and aback member for attachment to a load-bearing surface. A first armconnected to the back member forms a rotatable first joint. A second armconnected to the first arm forms a rotatable second joint. The frontmember connected to the second arm forms a rotatable third joint. Thefirst joint includes a first cam including a first lever and a firstshaft for connecting the back member to the first arm. The first leveris set in a first locked position and a first adjustment position. Thefirst cam allows rotation about an axis of the first joint when thefirst lever is set to the first adjustment position and the first camdoes not allow rotation about the axis of the first joint when the firstlever is set to the first locked position.

Furthermore, the first cam includes an adjustment dial. The first camallows rotation of the adjustment dial when the first lever is set tothe first adjustment position, and the first cam does not allow rotationof the adjustment dial when the first lever is set to the first lockedposition. The rotation of said adjustment dial increases or decreases atension of the first Joint. The first cam includes a first base, a firstpivot pin, and an adjustment dial. The first pivot pin is inserted intothe first lever and the first shaft to secure the first lever, the firstbase, and the first pivot pin to a first end of the first shaft. Thefirst adjustment dial is connected to a second end of the first shaft.The first locked position of the first lever is provided perpendicularto the first shaft, and the first adjustment position of the first leveris provided parallel to the first shaft. The second joint includes asecond cam including a second lever, a second shaft, and a tension pinfor connecting the first arm to the second arm. The second lever is setin a second locked position and a second adjustment position. The secondcam allows rotation about an axis of the second joint when the secondlever is set to the second adjustment position and the second cam doesnot allow rotation about the axis of the second joint when the secondlever is set to the second locked position. The second cam allowsrotation of the tension pin when the second lever is set to the secondadjustment position, and the second cam does not allow rotation of thetension pin when the second lever is set to the second locked position.The rotation of the tension pin increases or decreases a tension of thesecond joint. The second cam includes a second base and a second pivotpin. The tension pin is inserted into the second shaft. The second pivotpin is inserted into the second lever and the tension pin to secure thesecond lever, the second base, the second pivot pin and the tension pinto the second shaft. The tension pin is a screw.

In another embodiment of the present invention, a cantilever mounting,device includes a front member on which an object is mounted and a backmember for attachment to a load-bearing surface. A first arm connectedto the back member forms a rotatable first joint. A second arm connectedto the first arm forms a rotatable second joint. The front memberconnected to the second arm forms a rotatable third joint. The thirdjoint includes a third cam including a third lever and a third shaft.The third lever is set in a locked position and an adjustment position.The third cam allows rotation about the axis of the third joint when thethird lever is set to the adjustment position. The third cam does notallow rotation about an axis of the third joint when the third lever isset to the locked position.

Furthermore, the third cam allows rotation of the third shaft when thethird lever is set to the adjustment position, and the third cam doesnot allow rotation of the third shaft when the third lever is set to thelocked position. The rotation of the third shaft increases or decreasesa tension of the third joint. The third cam includes a third base, athird pivot pin, a top pivot, and a bottom pivot. The third pivot pin isinserted into the third lever and the third shaft to secure the thirdlever, the third base, and the top pivot pin to a first end of the thirdshaft. The bottom pivot is connected to a second end of the third shaft.A tilt link is connected to the top pivot and the bottom pivot. The tiltlink connects the third cam to the front member. The tilt link providesrotation about an axis perpendicular to the axis of the third joint.

A method for adjusting the position of a cantilever mounting deviceincludes applying force to a first lever of a first cam for reducing atension of a first joint and for setting the first lever to a firstadjustment position. A first arm is rotated relative to a back memberabout the first joint when the first lever is in the first adjustmentposition. Force is applied to the first lever for increasing the tensionof the first joint and for setting the first lever to a first lockedposition such that the first arm is locked in place relative to the backmember.

Furthermore, an adjustment dial of the first cam is rotated to reducethe tension of the first joint when the first lever is set to the firstadjustment position. Force is applied to a second lever of a second camfor reducing a tension of a second joint and for setting the secondlever to a second adjustment position. A second arm is rotated relativeto the first arm about the second joint when the second lever is in thesecond adjustment position. Force is applied to the second lever forincreasing the tension of the second joint when the second lever is inthe second adjustment position. Force is applied to the second lever forincreasing the tension of the second joint and for setting the secondlever to a second locked position such that the second arm is locked inplace relative to the first arm. Force is applied to a third lever of athird cam for reducing a tension of a third joint and for setting thethird lever to a third adjustment position. A front member is rotatedrelative to the second arm about the third joint when the third lever isin the adjustment position. Force is applied to the third lever forincreasing the tension of the third joint and for setting the thirdlever to a third locked position such that the front member is locked inplace relative to the second arm. The front member is tilted about anaxis perpendicular to the third joint.

Other features and advantages of the invention will be apparent from thefollowing detailed description, taken in conjunction with theaccompanying drawings which illustrate, by way of example, variousfeatures of embodiments of the invention.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view of one embodiment of a cantilever mountingdevice of the invention.

FIG. 2A is a perspective view of one embodiment of a front plate of theinvention.

FIG. 2B is a perspective view of one embodiment of a back plate of theinvention.

FIG. 2C is a perspective view of one embodiment of a lower arm of theinvention.

FIG. 2D is a perspective view of one embodiment of an upper arm of theinvention.

FIG. 3 is an exploded view of one embodiment of a shoulder joint of theinvention.

FIG. 4A is a partial side view of one embodiment of a lever of theinvention.

FIG. 4B is an exploded view of one embodiment of a shoulder cam of theinvention.

FIG. 5A is a side view of one embodiment of an elbow joint of theinvention.

FIG. 5B is an exploded view of one embodiment of an elbow cam of theinvention.

FIG. 5C is a sectional view of one embodiment of an elbow joint of theinvention.

FIG. 6A is a side view of one embodiment of a wrist joint of theinvention.

FIG. 6B is side view of one embodiment of a wrist cam of the invention.

FIG. 6C is an exploded view of one embodiment of a wrist cam of theinvention.

FIG. 6D is a sectional view of one embodiment of a wrist joint of theinvention.

FIG. 6E is an exploded view of one embodiment of a bottom pivot of thewrist cam of the invention.

FIG. 7 is an exploded view of one embodiment of a wrist joint of theinvention.

FIG. 8 is a perspective view of one embodiment of a double armcantilever mounting device of the invention.

DETAILED DESCRIPTION OF THE INVENTION

One embodiment of a mounting device 100 is illustrated in FIG. 1 and canbe used to display a flat panel television against a wall in a homeentertainment center. Mounting device 100 is a cantilever style devicethat includes a front member such as a front plate 10 for mounting aflat-panel display, electronic device, or any other object suitable formounting. Opposite front plate 10 is provided a back member or backplate 20 for attaching mounting device 100 to a support structure ableto bear the weight of mounting device 100 and mounted object. Thesupport structure is preferably a wall but can be any load-bearingstructure. Plastic caps 1 and 2 are provided to cover the top and bottomportions of back plate 20. Caps 1 and 2 conceal screws (not shown)provided to attach back plate 20 to a wall, and will be discussed inmore detail with respect to FIG. 2B. A lower arm cap 3 is optionallyprovided below lower arm 30 to conceal back plate 20 from view.

Mounting device 100 includes articulating joints analogous to a humanarm and can be described using similar terminology. For example, a firstend of a lower arm 30 is attached perpendicularly to back plate 20 by ashoulder cam 50 to form a shoulder joint that acts as a hinge forrotation of the lower arm about the shoulder joint. Similarly, an elbowjoint is formed by an elbow cam 60 where a first end of an upper arm 40attaches to a second end of lower arm 30. The second end of upper arm 40connects to front plate 10 at wrist cam 70 to form a wrist joint thatallows front plate 10 to pivot side-to-side about an axis of the wristjoint. Each of the shoulder, elbow, and wrist joints has a range ofmotion that allows mounting device 100 to be adjusted as desired by auser. The shoulder, elbow, and wrist joints rotate in the same plane andmay also be referred to as respective first, second, and third joints.

FIGS. 2A-2D illustrate the components of mounting device 100 in greaterdetail. FIG. 2A shows front plate 10 provided with object mounting holes11 for mounting objects such as a flat panel display, mounting holes 12for securing front plate 10 to the wrist joint, and a lip 13 to securefront plate 10 to mounting device 100, as will be discussed later. FIG.2B illustrates back plate 20 including wall mounting holes 21 and 22,and lower arm mounting holes 23 and 24. The first end of lower arm 30 isplaced between holes 23 and 24, and shoulder cam 50 is inserted throughhole 23 to secure lower arm 30 to back plate 20. Furthermore, frontplate 10 and back plate 20 can be made from steel. In particular, theback plate can be formed of cast steel having a tensile strength of atleast 70,000 psi. Lower arm 30 is illustrated in more detail in FIG. 2C,and includes a first end 31 and second end 33 having hollow cylinders.Shoulder cam 50 and elbow cam 60 fit into holes 31 and 33, respectively,as seen in FIG. 3. Hooks 32 allow cap 3 to attach to and cover lower arm30. FIG. 3D shows the structure of upper arm 40 including a first end 41and second end 42. The upper and lower arms can be implemented as atruss structure formed of plastic resin such as nylon that provides highstrength and low weight.

FIG. 3 is an exploded view of a shoulder joint of the inventionincluding lower arm 30, shoulder cam 50 and back plate 20. As shown inFIG. 3 and 4B, shoulder cam 50 includes a lever 51, pivot pin 52, base53, pivot shaft 54 and adjustment dial 55. Shoulder cam 50 is placedthrough mounting holes 22 and 23 of back plate 20 and through hollowcylinder 31 of lower arm 30. The bottom portion of pivot shaft 54includes a threaded portion which screws into adjustment dial 55. Thebottommost portion of shaft 54 is secured into back plate 20 by hole 22.Adjustment dial 55 is attached to shaft 54 and is provided between thebottom of first end 31 and mounting hole 22. The top portion of pivotshaft 54 includes a hole for pivot pin 52. Base 53 is provided with ahole for sliding over the top of pivot shaft 54. Lever 51 rests abovebase 53 and includes a cavity for pivot shaft 54 to protrude into. Inthe assembled shoulder cam 50, pivot pin 52 is provided throughcorresponding holes in lever 51 and the hole of pivot shaft 54. Pivotpin 52 secures lever 51, base 53 and shaft 54 together.

FIG. 4A shows the adjustment position of the cam of the presentinvention. When lever 51 is unlocked and set vertically so as to beparallel to pivot shaft 54, enough tension is released in the shoulderjoint so that adjustment dial 55 can be rotated to increase or decreasethe tension between lower arm 30 and back plate 20 at the shoulderjoint. The user simply pushes the lever up and down to move from thelocked position to the unlocked adjustment position. In this manner,lower arm 30 and back plate 20 can rotate about the shoulder joint.Furthermore, adjustment dial 55 can be rotated to either allow or notallow rotation of the shoulder joint. The joint is rotated by the userrotating lower arm 30 about the shoulder joint. Once set at a desiredposition, the lever is pushed down to increase the tension and locklower arm 30 in place. However, when lever 51 is set horizontally to thelocked position, the tension of the shoulder joint is strong enough toprevent rotation of adjustment dial 55. Furthermore, lever 51 in thelocked position can prevent rotation of lower arm 30 and back plate 20about the shoulder joint. Thus, the use of lever 51 and adjustment dial55 allows a user to adjust the position and tension of the shoulderjoint with an economy of motion and without the need for tools. Asdescribed in more detail below, the levers of the elbow cam and wristcam operate in a similar manner to provide an adjustment position andlocked position.

FIG. 5A provides a side view of mounting device 100 with a focus on theconnection of lower arm 30 to upper arm 40 at the elbow joint by elbowcam 60. Similar to shoulder cam 50, elbow cam 60 includes a lever 61,pivot pin 62, base 63 and fastening shaft 65. Elbow cam 60 furtherincludes a tension pin 64 and a base cap 66. Fastening shaft 65 isinserted into first end 41 of upper arm 40 and through second end 33 oflower arm 30. Fastening shaft 65 is secured to the bottom of lower arm30 by a base cap 66. Tension pin 64 is screwed into the top of fasteningshaft 65 and includes a hole for pivot pin 62. The operation of elbowcam 60 is similar to that of shoulder cam 50. For example, when lever 61is provided in a horizontal locked position, the downward force of lever61 locks the position of lower arm 30 and upper arm 40 in place toprevent movement of the arms and rotation of the elbow joint. However,when lever 61 is set to the vertical adjustment position, the tensionbetween lever 61 and base 63 is relieved such that a user canoperatively rotate upper arm 40 relative to lower arm 30 about the elbowjoint. FIG. 5C provides a more detailed view of elbow cam 60.

FIG. 5C illustrates a sectional view of the elbow joint. As discussedabove, fastening shaft 65 is provided in the hollow end cylinders ofupper arm 40 and lower arm 30. Furthermore, tension pin 64 is insertedthrough pivot pin 62, base 63 and the top of fastening shaft 65 tosecure those elements together. Tension pin 64 can be a threaded screwand is screwed into fastening shaft 65 to increase or decrease the elbowtension. After lever 61 is pushed and unlocked at an adjustment positionthat reduces the tension in the elbow joint, a user is then able torotate base 63 and lever 61 to either loosen or tighten tension pin 64to adjust the tension of the elbow joint further. When lever 61 is inthe locked position, tension pin 64 does not rotate. If the elbow jointis unlocked or loosened, the user is able to rotate and reposition lowerarm 30 and upper arm 40 with respect to each other about the elbowjoint. When tightened by rotating base 63 and locked by pushing down onlever 61, the angle of the arms is set in place. Thus, after unlockingthe elbow cam 60, lever 61 and base 63 can be rotated to adjust thetension of cam 60 to allow lower arm 30 and upper arm 40 to moverelative to each other as desired by a user.

The wrist joint is now described. FIG. 6A is a side view of the wristjoint including wrist cam 70, front plate 10, and tilt links 75 and 79connecting thereto. Wrist cam 70 includes a lever 71, base 73, pivotshaft 76, top pivot 77 and bottom pivot 78. Front plate 10 is connectedto wrist cam 70 via a mounting plate 14 (see FIG. 7) and tilt links 75and 79.

As shown in the exploded schematic view of FIG. 7, each of the tiltlinks 75 and 79 is inserted through corresponding holes of mountingplate 14 to attach wrist cam 70 to front plate 10. Mounting plate 14 isthen secured to lip 13 and mounting holes 12 of front plate 10. Tiltlinks 75 and 79 allow the front plate to adjustably pivot up and downalong an axis perpendicular to the wrist joint. Top tilt link 75 isconnected to wrist cam 70 via top pivot 77. Bottom tilt link 79 isconnected to bottom pivot 78 at a bottom end of shaft 76. Furthermore,pivot shaft 76 includes a lower threaded portion screwed into bottompivot 78.

FIGS. 6B and 6C are side and exploded views of wrist cam 70 includingthe components of a lever 71, pivot pin 72, base 73, top pivot 77 andpivot shaft 76. Pivot shaft 76 is inserted into the top of second end 42and secured at the bottom of second end 42 by bottom pivot 78 (FIG. 6D).Bottom pivot 78 is provided just below upper arm 40. The top of pivotshaft 76 includes a hole for pivot pin 72. Base 73 and top pivot 77 areprovided with a central hole for sliding over the top of pivot shaft 76.Top pivot 77 is provided below the hole of shaft 76. Lever 71 restsabove base 73 and includes a cavity for pivot shaft 76 to protrude into.In the assembled wrist cam 70, pivot pin 72 is provided throughcorresponding holes in lever 71 and the hole of pivot shaft 76 to securethe lever 71, base 73, pivot pin 72 and shaft 76 together.

The operation of wrist cam 70 is somewhat similar to shoulder cam 50 andelbow cam 60. When lever 71 is provided in a horizontal locked position,the downward force of lever 71 locks the position of pivots 77 and 78 toprevent side-to-side movement of front plate 10 about an axis of thewrist joint. However, when lever 71 is pushed to the vertical adjustmentposition by a user, the tension between lever 71 and pivot shaft 76 isrelieved such that a user can then rotate lever 71 and base 73 todecrease the wrist joint tension to thereby rotate front plate 10 to adesired position.

FIG. 6D illustrates a sectional view of the wrist joint. As discussedabove, pivot shaft 76 is provided in second hollow cylinder end 42 andthe bottom portion of pivot shaft 76 has a threaded portion which screwsinto bottom pivot 78. When lever 71 is unlocked in the verticalposition, a user is able to rotate base 73, lever 71 and pivot shaft 76,to either loosen or tighten the tension of the wrist joint. If the wristjoint is unlocked or loosened, top link 75 and bottom link 79 can movesuch that the user is able to rotate and reposition front plate 10 withrespect to upper arm 40 about the wrist joint. When tightened and lockedby pushing the lever in the appropriate direction, the angle betweenfront plate 10 and upper arm 40 is locked in place. Shaft 76 is unableto rotate when locked. Thus, after unlocking wrist cam 70, lever 71 andbase 73 can be rotated to adjust the tension of wrist cam 70 to allowfront plate 10 to move side-to-side relative to upper arm 40. Moreover,the grip-like hollow space shown in pivot 77 of FIG. 6B indicates therange of motion of top tilt link 75 along the axis of the rotationperpendicular to the wrist joint.

The levers and bases of the cams, as well as pivots 77 and 78, arepreferably formed from plastic resin while pivot shaft 54, fasteningshaft 65, and pivot shaft 76 are preferably formed of high carbon steel.Furthermore, pivot shaft 54, fastening shaft 65 and pivot shaft 76should have a yield strength of at least 100,000 psi. The tilt links arepreferably formed from plastic resins and steel.

An alternative embodiment of the invention is now described withreference to FIG. 8. Mounting device 200 of FIG. 8 is a double armcantilever mounting device having a pair of wrist, elbow and shoulderjoints. In particular, mounting device 200 includes a back plate 220 andfirst and second front plates 210 and 211. First and second shouldercams 250 and 251 connect first and second lower arms 230 and 231 to backplate 220. A cap 201 is provided to cover the bottom of the lower arms.First and second upper arms 240 and 241 are provided and connect tofirst and second lower arms 230 and 231 by first and second elbow cams260 and 261. First and second front plates 210 and 211 are connected tofirst and second upper arms 240 and 241 by first and second wrist cams270 and 271. The double arm mounting device 200 allows a wide range ofadjustment for mounting objects of increased size/weight.

The particular embodiments of the invention described in this documentshould be considered illustrative, rather than restrictive. Modificationto the described embodiments may be made without departing from thespirit of the invention as defined by the following claims and theirequivalents.

1. A cantilever mounting device comprising: a front member on which anobject is mounted; a back member for attachment to a load-bearingsurface; a first arm connected to said back member to form a rotatablefirst joint; a second arm connected to said first arm to form arotatable second joint; said front member connected to said second armto form a rotatable third joint; wherein said first joint includes afirst cam including a first lever and a first shaft for connecting saidback member to said first arm; wherein said first lever is set in afirst locked position and a first adjustment position; wherein saidfirst cam allows rotation about an axis of the first joint when saidfirst lever is set to said first adjustment position, and said first camdoes not allow rotation about the axis of the first joint when saidfirst lever is set to said first locked position.
 2. The cantilevermounting device of claim 1, wherein said first cam includes anadjustment dial; and said first cam allows rotation of said adjustmentdial when said first lever is set to said first adjustment position, andsaid first cam does not allow rotation of said adjustment dial when saidfirst lever is set to said first locked position.
 3. The cantilevermounting device of claim 2, wherein the rotation of said adjustment dialincreases or decreases a tension of the first joint.
 4. The cantilevermounting device of claim 1, wherein said first cam includes a firstbase, a first pivot pin, and an adjustment dial; wherein said firstpivot pin is inserted into said first lever and said first shaft tosecure said first lever, said first base, and said first pivot pin to afirst end of said first shaft; wherein said adjustment dial is connectedto a second end of said first shaft.
 5. The cantilever mounting deviceof claim 1, wherein the first locked position of said first lever isprovided perpendicular to said first shaft, and the first adjustmentposition of said first lever is provided parallel to said first shaft.6. The cantilever mounting device of claim 1, wherein said second jointincludes a second cam including a second lever, a second shaft, and atension pin for connecting said first arm to said second arm; whereinsaid second lever is set in a second locked position and a secondadjustment position; wherein said second cam allows rotation about anaxis of the second joint when said second lever is set to said secondadjustment position and said second cam does not allow rotation aboutthe axis of the second joint when said second lever is set to saidsecond locked position.
 7. The cantilever mounting device of claim 6,wherein said second cam allows rotation of said tension pin when saidsecond lever is set to said second adjustment position, and said secondcam does not allow rotation of said tension pin when said second leveris set to said second locked position.
 8. The cantilever mounting deviceof claim 6, wherein the rotation of said tension pin increases ordecreases a tension of the second joint.
 9. The cantilever mountingdevice of claim 6, wherein said second cam includes a second base and asecond pivot pin; wherein said tension pin is inserted into said secondshaft; wherein said second pivot pin is inserted into said second leverand said tension pin to secure said second lever, said second base, saidsecond pivot pin and said tension pin to said second shaft.
 10. Thecantilever mounting device of claim 6, wherein said tension pin is ascrew.
 11. A cantilever mounting device comprising: a front member onwhich an object is mounted; a back member for attachment to aload-bearing surface; a first arm connected to said back member to forma rotatable first joint; a second arm connected to said first arm toform a rotatable second joint; said front member connected to saidsecond arm to form a rotatable third joint; said third joint includes athird cam including a third lever and a third shaft; wherein said thirdlever is set in a locked position and an adjustment position, whereinsaid third cam allows rotation about the axis of the third joint whensaid third lever is set to said adjustment position, and said third camdoes not allow rotation about an axis of the third joint when said thirdlever is set to said locked position.
 12. The cantilever mounting deviceof claim 11, wherein said third cam allows rotation of said third shaftwhen said third lever is set to said adjustment position, and said thirdcam does not allow rotation of said third shaft when said third lever isset to said locked position.
 13. The cantilever mounting device of claim11, wherein the rotation of said third shaft increases or decreases atension of the third joint.
 14. The cantilever mounting device of claim11, wherein said third cam includes a third base, a third pivot pin, atop pivot, and a bottom pivot; wherein said third pivot pin is insertedinto said third lever and said third shaft to secure said third lever,said third base, and said top pivot pin to a first end of said thirdshaft; wherein said bottom pivot is connected to a second end of saidthird shaft.
 15. The cantilever mounting device of claim 11, furthercomprising: a tilt link connected to said top pivot and said bottompivot; wherein said tilt link connects said third cam to said frontmember; wherein said tilt link provides rotation about an axisperpendicular to the axis of said third joint.
 16. A method of adjustinga cantilever mounting device comprising the steps of: applying force toa first lever of a first cam for reducing a tension of a first joint andfor setting said first lever to a first adjustment position; rotating afirst arm relative to a back member about the first joint when saidfirst lever is in the first adjustment position; applying force to saidfirst lever for increasing the tension of the first joint and forsetting said first lever to a first locked position such that said firstarm is locked in place relative to said back member.
 17. The method ofadjusting the cantilever mounting device of claim 16, further comprisingthe steps of: rotating an adjustment dial of said first cam to reducethe tension of the first joint when said first lever is set to the firstadjustment position.
 18. The method of adjusting the cantilever mountingdevice of claim 16, further comprising the steps of: applying force to asecond lever of a second cam for reducing a tension of a second jointand for setting said second lever to a second adjustment position;rotating a second arm relative to said first arm about the second jointwhen said second lever is in the second adjustment position; applyingforce to said second lever for increasing the tension of the secondjoint and for setting said second lever to a second locked position suchthat the second arm is locked in place relative to said first arm. 19.The method of adjusting the cantilever mounting device of claim 16,further comprising the steps of: applying force to a third lever of athird cam for reducing a tension of a third joint and for setting saidthird lever to a third adjustment position; rotating a front memberrelative to said second arm about the third joint when said third leveris in the third adjustment position; applying force to said third leverfor increasing the tension of the third joint and for setting said thirdlever to a third locked position such that the front member is locked inplace relative to said second arm.
 20. The method of adjusting thecantilever mounting device of claim 19, further comprising: tilting thefront member about an axis perpendicular to the third joint.